GT1 thru GT7 are the order patterns for the G8 GT. 1 is cloth, no options; 2 is cloth, 18" all seasons; 3 is leather, premium package, and sunroof; 4 is leather, premium package, 18" all seasons; 5 is leather, premium package, sunroof, and 18" all seasons; 6 is leather, premium package, and sport package; 7 is leather, premium package, sport package, and sunroof